1. Replenish energy: People will consume a lot of energy after exercise, and milk is rich in high-quality protein and carbohydrates, which can quickly replenish energy and help the body recover.

2. Promote muscle growth: protein in milk is necessary for human body to repair and build muscle tissue. Adequate intake of protein after exercise is helpful for muscle growth and repair.

3. Improve immunity: Milk is rich in vitamins and minerals, such as calcium, phosphorus and zinc, which can enhance immunity and reduce fatigue after exercise.

4. Relieve pain: Amino acids in milk can help the body to produce anti-inflammatory substances, such as glutamic acid and tyrosine, which can relieve muscle pain after exercise.

5. Protect bones: Milk is rich in calcium, which helps to keep bones healthy and prevent fractures and osteoporosis.

In a word, drinking milk after fitness can provide necessary nutrition for the body, help the body recover, promote muscle growth, improve immunity, relieve soreness and protect bones. But it should be noted that milk is not suitable for everyone. Some people may be lactose intolerant or allergic to milk. Please make sure that you have no such problems before drinking milk.